Planetary Nebula

ESO 456-67

    This planetary nebula, named ESO 456-67 is located in the constellation Sagittarius.  It is in the southern sky and shows clearly the different layers of material which were expelled by the star at the center.  It is located 10,000 light years from Earth.  

Biography Sources

Maria Mitchell

Ragan, Gay A. "Mitchell, Maria." Mathematics. Ed. Barry Max Brandenberger, Jr. Vol. 3. New York: Macmillan Reference USA, 2002. 51. Gale Virtual Reference Library. Web. 26 Feb. 2013.

"Mitchell, Maria." Complete Dictionary of Scientific Biography. Vol. 9. Detroit: Charles Scribner's Sons, 2008. 421-422. Gale Virtual Reference Library. Web. 26 Feb. 2013.

"Maria Mitchell." Science and Its Times. Ed. Neil Schlager and Josh Lauer. Vol. 5: 1800 to 1899. Detroit: Gale, 2000. 498. Gale Virtual Reference Library. Web. 26 Feb. 2013.

"Maria Mitchell." Encyclopedia of World Biography. 2nd ed. Vol. 11. Detroit: Gale, 2004. 61. Gale Virtual Reference Library. Web. 26 Feb. 2013.

APOD 3.6

20 Feb 2013 Saturn's Hexagon and Rings

    This feature of hexagonal clouds on Saturn is very odd and scientists do not know the reason for its formation.  It was discovered during the 1980s when the Voyager flew by the planet.  No similar features have since been sighted anywhere in the Solar System.  The South pole of Saturn is known as having a strange rotating vortex and this image shows the North Pole with this mysterious cloud pattern.  This image was taken by the Cassini Spacecraft which reached Saturn in 2004.  This shows that the clouds have been active for over 20 years since the Voyager sighting.  This feature of the planet is very massive as four Earths could easily fit inside of it.  

APOD 3.5

12 Feb 2013 Reflected Aurora Over Alaska

An aurora is a glow in the upper atmosphere created by energy particles entering the atmosphere from space.  The magnetosphere provides the particles that create auroras seen from Earth.  The colors are determined by the composition and density of the atmosphere where it is created.  A subvisual aurora is one which cannot be seen with the naked eye and requires a camera to view.  This image features both visual and subvisual auroras; the green were visible to the naked eye but the red areas only appeared in the captured image.  The reason for this increased visibility through the lens of a camera is that cameras offer more exposure time than the human eye which only collects light for fractions of seconds at a time.  This image was taken in Anchorage, Alaska and features the Pleiades star cluster and Jupiter.  These red and green auroras were most likely created by oxygen particles.

APOD 3.4

NGC 6822: Barnard's Galaxy

         

    The galaxy pictured, NGC 6822, is classified as small despite the fact that it is over 7,000 light-years across.   It is also called Barnard's Galaxy and has a magnitude of 9.3.  It contains the Bubble Nebula and is 1.5 million light-years away.  The blue stars are relatively young while the pinkish areas are where new stars are forming.  This image was taken using the Lowell Amateur Research Initiative with the Lowell Observatory.                                                                                  

Labeled Moon Diagram

APOD 3.3

26 Jan 2013 Alaskan Moondogs

    

    This image was taken in Miller Creek, Alaska, on January 17th.  This moon is in its first quarter phase and clearly has a halo around it in the sky.  This halo was created by ice crystals which are falling in the atmosphere and create a giant lens reflecting the light from the moon. On the left and right, moondogs can be seen. They are similar to sundogs but are created by the moon reflecting light on icy crystals in the atmosphere.  The scientific name for this apparition is paraselenae.  The moon must be observed from an angle equal to or greater than 22 degrees and the ice crystals must be of hexagonal shape for moondogs to be visible.